Improvement in file-cutting machines



T. E. THURSTON.

. File Cutting Machine,

Patented July 14. 1868.

gem/0W UNITED STATES THOMAS E. THURSTON, OF NEWARK,

PATENT OFFICE.

NEW JERSEY, ASSIGNOR TO HIMSELF AND JAMES KEARNEY, OF SAME PLACE.

IMPROVEMENT IN FILE-CUTTING MACHINES.

To all whom it may concern:

Be it known that I, THOMAS E. THURSTON, of the city of Newark, in thecounty of Essex and State of New Jersey, have made certain Improvementsin the Construction of Va rious Parts of a FileGutting Machine, (forwhich a patent was granted to Elisha O. Potter, assignor to himself andU. A. VVarland, November 8, 1864;) and I hereby declare the following tobe a full and exact description of the same, reference being herein hadto the drawings that accompany this specification as part of the same.

My joint assignee, JAMES KEARNEY, having purchased a right of use with afile-cut ting machine, found its defects to be such as to preventperfect work and to materially reduce the expected reasonable profitsthat induced t-hepurchase. Having by time, thought, experience, andexpense remedied the defects, I proceed to show theimprovements wedesire to secure.

In the drawings, Figure l is a perspective view of the machine. Fig. 2is the support and guide for the hammer and of the carrier of thechisel-holder. Fig. 3 is the carrier of the chisel-holder and the holderof the chisel. Fig. 4 shows various views of parts of the chisel-holder.

The part A as constructed. in the original machine did not inclose theguide-pieces a and I), nor was there any means of graduating theirpressure upon the sides of the hamlner or the carrierot'the'chisel-holder. Entire dependence had to be upon the bolts 0 andd, which in practice was found to be insufficient for the steadiment andadjustability required.

In Fig. 2 is shown the part A with an inclosure, e, cast therewith as anintegral part thereof, the set-screws l 2 3 4 holding the guide-piecesimmovable sidewise, leaving them adjustable at pleasure, the two bolts 0and d confining them to the back, as in the original machine.

The hammer B has a lifting-stem and footthat are in the originalmachine, held by the two set-screwsgandh. These not being found inpractice reliable, I have laid aside, and have I substituted the hollowscrew-stein and setscrew shown by D, Fig. 2, by which the desiredlifting of the hammer by the cam f is obtained, and also as the edge ofthe chisel rests upon the file-blank when the blow is struck, and as thechisels get shortened by grinding to sharpen, I am provided with a meansof adjusting with the utmost nicety the distance between the ham mer andthe head of the chisel and of retaining it immovable from thejarring ofthe machine when at work.

In the original machine the sliding carrier E has the foot-piece F heldupon it by screwbolts, which soon work loose. As an indispensableimprovement, I have the foot-piece F cast as an integral part of E. Thechiselholder G is attached to F by the two screws iand j, which, beingmovable in the curved slots 70, provide for adjusting the angle of thechisel H the file under process of cutting may require.

In the original machine the basepiece of the chisel-holder G has asemicircular concave,m, open on both sides, in which the convexsemicircle n, to which the chisel is attached, is held to m by twoscrews, one of which is shown by s, Fig. 4, the part of G on which thescrewheads rests being a segment of a circle de scribed from the samecenter as the convex n, and having slots for the screws to more in, w,one on each side of the slot 1,.through which the head of the chisel Hpasses. In practice the convex n was found not to be sutficientlysteadied by the screws for the correct performance of fine work. As anecessary improvement I either screw a p1ate,p, one on each side of G,close to the sides of the convex n, or have the sides cast upon G, as atq, forming an integral part thereof.

As an additional stay or steadiinent to A, I attach to e theadjustableroller u, that runs upon the piece '1 which is fastened to theblock 2, upon which the file-blank tis held under the chisel H.

As by these five items of improved construction the machine is renderedpractically available for profitable use, I therefore desire to securethem by Letters Patent.

1 claim- 1. Plate A, having the part 0 cast or forged and used in afile-cutting machine which has therewith, in combination with parts a band thereon the improved part 6, all constructed B and E, all combinedand arranged in the l substantially as hereinabove set forth.

manner and for the purpose set forth. THOMAS E. THURSTON.

2. The improved adjustable stem D, the im- Attest: j

proved parts E and F, the improved part Gr, W. M. GOODING,

and the adjustable roller u, when arranged EDWARD OOLLVER.

